The present invention relates to an electric steam iron of the type comprising an injection device for letting a certain amount of water flow into a vaporization chamber from which the steam which is formed escapes through openings in the sole-plate.
Steam irons of this type allow dispensing of a certain moderate amount of steam which can be regulated within certain limits to effect ironing. However, for special kinds of work a considerable surplus of steam is needed for a short time. It is known to use in this case an auxiliary injection device which brings in water in accordance with the amount of steam needed.
If this relatively large surplus of water is admitted directly into the vaporization chamber of a conventional iron, there is a risk of producing an abundance of scale and there is the risk of incomplete vaporization with the deposit of water on the pieces to be ironed and possibly the formation of scale deposits. In addition, the projection of little droplets of water can cause spots.
It has been proposed to effect an auxiliary injection in an auxiliary chamber formed by a conduit of great length and small cross section which is provided with baffles. This allows retardation of the water flow and facilitates total vaporization. The abundant vaporization however which occurs in these narrow conduits with baffles produces a rapid and unacceptable scale deposit which is very difficult to eliminate.